Exhaust valve for lamp making machines



'A ril 12, 1938. D. MULLAN 2,113,798

EXHAUST VALVE FOR LAMP MAKING MACHINES Filed June 27, 1936 sSheets-Sheet 1 INVENTOR ,0. Mall/9 21 .9.

ATTORNEY April 12, 1938.

EXHAUST VALVE FOR LAMP MAKING MACHINES 3 Sheets-Sheet 2 D. MULLAN.F'iled June 27, 1936 INVENTOR April 12, 1938. D. MULL-AN ,1 3,7

EXHAUST VALVE FOR LAMP MAKING MACHINES Filed June 27, 1956 sSheets-Sheet :5

V v lNVE TOR A a MHZ/UV ATTORN Patented Apr. 12, 1938 EXHAUST VALVE FORLAMP MAKING MACHINES Daniel Mullan, Kearny, N. .L, assignor, by mesneassignments; to Westinghouse Electric and Manufacturing Company, EastPittsburgh, Pa.,

a corporation of Pennsylvania Application June 27, 1936, Serial No.87,702 9 Claims. (01. 176-2) This invention relates to machines 'forexhausting and gas-filling hollow bodies, and particularly to such usedfor the manufacture of incandescent electric lamps or similar devices.

Exhaust machines used in the lamp making industry usually comprise arotary conveyor on which a plurality of what are termed exhaust portsare arranged along the periphery of the conveyor. The conveyor is, infact, a rotary valve including top and bottom valve sections in the formof circular plates.

The valve plates are relatively movable and the relative movement of the.plates, by reason of suitable channels and ducts, results in an open--ing and a closing of vacuum lines to which hollow bodies such as lampbulbs or the like a e con-' nected for an exhausting operation.

It will be readily appreciated that under the continuous operation towhich machines of the abovetype are subjected, the valve sections mustbe so constructed as to operate with a minimum amount of wear, andfurther that any. concentrated wear on the opposing surfaces of thevalve sections results in leakage with the conapart and as this distancewas necessarily long to provide adequate contact for maintaining a seal,each device was cut oif from ,the pumps for a relatively long periodwhen traveling through a stage of exhaust. This resulted in a drop inthe vacuum in the device at each cut-oft period and imposed extra workon the pumps to bring the device to the required vacuum.

It has been proposed to make the valve sections with elongated slots orports arrangedin close proximity to reduce the distance of cut-off.,This expedient, however, reduced the contact area between the ports andafter continued use slight grooves would wear. between the ports,bringing about a condition which-was detrimental to the efficientoperation of the machine. I

It is an object of the present invention to provide an improved form ofexhaust valve in which the time of cut-ofi is reduced.

Another object of the invention is to provide valve plates for anexhaust machine in whichthe valve ports are so arranged as to provide asubstantially continuous exhausting operation.

55 Another object otthe invention is to rovide a valve for an exhaustmachine in which multiple valve ports are provided for each device topermit an arrangement whereby such ports may be moved successively intocommunication with a vacuum line to give a substantially continuousexhausting operation. I

Another object of the invention is to provide a valve arrangement inwhich asubstantially continuous exhausting operation may be performedwithout subjecting the valve members to excessive wear.

Other objects and advantages of the invention will be more clearlyunderstood by reference to the following description together with theaccompanying drawings in which:

Fig. 1 is a plan view of a machine constructed in accordance with thepresent invention;

fFig..2 is a, diagrammatic plan view of the machine shown in Fig. 1 butshowing the arrangement of the pumps and vacuum lines or manifolds;

Fig. 3 is a view taken on line IIIIII in Fig. 1; Fig. 4 is a view' takenon line IV-IV in Fig. 3 looking at the under side of the top valvesection; Fig. 5 is a view taken on line VV in Fig. 4; Fig. 6 is a viewtaken on line VIVI in Fig. 3 looking at the top of the bottom valvesection; Fig. 7 is a view taken on line VIIVII in Fig. 6; Fig. Bis aview taken on line VIII- -VIII in Fig. 6; and

Fig. 9 is a fragmentary view. showing the relative positions of ports inan upper valve section and slots in. a lower valve section as one pairof ports is leaving one slot and moving over another.

' I The present invention may be embed. .d in any inary pump, andexhausted as they travel: that is, they are moved from one port toanother while on the preliminary exhaust pump.

The same procedure is followed when the devices are subjected to thesecond pump or final exhaust. In exhaust machines as heretoforeconstructed, a single row of ports was provided and the device movedsuccessively'from one port having flat opposed surfaces 33 and 34 withan In accordance with the present invention each conduit fora device isprovided with a plurality of ports arranged to communicate with aplurality of slots disposed in two circular rows and in staggeredrelation. Thus as the conveyor moves and the valve is operated,communication is had with the pump. During the travel of a device fromone port to another, one port is closed while the other is opened, andsince the ports may thus be widely separated, an effective seal is maintained.

The invention may be applied to an exhaust machine comprising aconveyor, indicated as a Whole by the reference character 9, having acentral rotatable hub or shaft l6 on which is mounted a carrier plate orflange H suitably fastened to the shaft l6 and rotatable therewith.

The shaft is provided with a worm wheel i2 and mounted for rotation inbearings l4 and I4 on a stationary supporting frame or bracket IS. Aworm i6 on a shaft I1 is disposed in mesh with worm wheel l2. The shaftI1 is provided with a pulley l8 over which a belt I! leads to a pulley2| on shaft 22 of a motor 23. This driving mechanism from the motorprovides a continuous drive. It will be understood, however, that anintermittent operation may be provided if desired by using means such asa Geneva drive which is well known and common practice in connectionwith machines of the present character.

Th present invention may be used with either type of machine and theconstruction shown has been selected for the purpose of disclosing theadvantages of the present invention when applied to a machine in whichthe work parts are moved continuously to attain high-speed production.In the structure shown, a plurality of what are termed exhaust ports 24are positioned adjacent to'and in spaced relation around the peripheryof the plate ll. Sixteen ports are shown in the drawings although moreor less may be employed. Each port includes a flexible tube- 26 toreceive an exhaust tube 26 of a bulb 21 suitably supported in a holder26.

A bulb holder and an exhaust port is usually termed a head and the headsare as a whole indicated by the reference numeral 29. The heads are ofsimilar construction and inasmuch as their structure is well known inthe art, it is believed that the showing made is sufficient. As theheads move with the conveyor, the supported bulbs are progressivelyconnected to the vacuum pumps by means of a valve comprising a topsection 3| and a lower section 321 These valve sections are in the formof rings interposed oil seal fed through passage 36. The top valvesection moves with the shaft III and is secured to the plate H by dowelpins 35. Pressure springs 36 serve to hold the upper section in firmrelation to the lower section which is vided with a T-member 36connecting a conduit 39 to a gas inlet} of the valve and with a rubbernipple 4| and a conduit 42 leading to the valve vacuum inlet.

An oil trap 40 is provided between the nipple and the conduit 42. Eachnipple is provided with a cut-off means comprising a cam 43 movableabout a pin 44 so that at the proper place during movement of theconveyor the cam is operated to pinch the nipple 4| and close thepassage through conduit42, as for example; when the exhaust line isclosed and. gas is admitted or withdrawn from the bulb, or for otherpurposes. The opening and closing of the exhaust line by means of pinchcocks is well known in machines of the present type and no detaileddescription of this operation is given.

A machine of the present type is usually provided with a duplex pumpincluding a preliminary pump 45 and a final pump 46.

The pump 45 is in communication with pump 46 through conduit 41 andintermediate the pumps is a conduit 48 controlled by valve 49 andleading to a manifold having branch conduits 52, 52', 52 52 and 52*,connected to the valve unit. A leak detector 53 is also connected to themanifold 5i. This leak detector may be of any well-known type andis'not'shown in detail. The pump 46 connects with a manifold 54 throughconduit 55 which leads to the manifold 54 and is provided with valve 56.This manifold has branch conduits 51, 51', 51 51 51 51 51 and 57",connected to the valve unit.

During the process of evacuation the bulbs are flushed with gases suchas oxygen and nitrogen and when gas lamps are made a final filling ofargon gas is provided. As shown in Fig. 2, three sources of gas conduitsare shown and indicated by the reference characters 56, 59, and 6|controlled by valves 62, 63, and 64 respectively. The gas conduitssupply nitrogen, oxygen, and argon, or any other desired gas or gases.These gases may be fed to the valve unit at different stages of theconveyor, but inasmuch as the present valve may be used with or withoutthe introduction of gas in the lamp, further description of the gasflushing or filling is deemed unnecessary.

As above pointed out, the present valve unit is constructed to provide asubstantially continuous duit 42. The lower valve section is providedwith an outer row of slots 68', 68 68 66 68 and 68 and an inner row ofslots 69', 69 69 69 69 69 and 69 The slots of one row are staggered withrespect to the slots of the other row and at certain positions the endsof the opposite slots are in close proximity to a. common radial line sothat if, for example, port 66 is being moved over the end of a slot theport 65 will be leaving a slot and the distance between adjacent ends ofthe slots will be slightly smaller than the diameter of the ports. SeeFig. 6 which shows the relative positions of ports 66 and 65 in dottedlines.

It will be obvious that the relative positions of the ends ofthe'slotswith respect toa radial line is dependent on the diameter ofthe ports 66 and 65. Thus, as the upper valve section moves,- one of theports 66 or 65 is over a slot in the lower valve section While the otherport is closed. This gives a continuous exhaust operation; avoiding anydead" or cut-off stages. I I" The relative positions of upper valveports and the lower valve slots are shown more clearly in Fig. 9 whichis diagrammatic. It will be noted Thus the operation of exhausting'maybeconthat the slots and ports are disposed in what may be termeddifferent concentric circles X, X, and are so arranged that a row'ofports moves over a row of slots. Each pair. of ports leading from anexhaust head is arranged so that one port is on a circle concentric withthat of the other port, the centers of both ports being disposed on acommon radial line Y. As'shown,

the slots are so arranged that as a port moves from the end of one slot,another port is moving into communication with another slot. Theadjacent ends of the, slots are thus positioned so that the exhaust headis in continual communication with the pump during a predeterminedmovement of the valve. With this arrangement of ports and slots, it ispossible to maintain an effective seal since the contacting area of thevalve sections between the ports and slots is relatively large.

Although the valve slots may be arranged to overlap to such anextent'that the exhaust operation is continuous, it will be evidentthat, if desired, 'the slots may be so arranged that the bulb may becut-off from the pump for a brief period by a variation in thearrangement of the ports and slots.

As will be noted from the drawings (see Fig. 1), the bulb is loaded orinserted. into an exhaust port at A. The conveyor then moves and thebulb is connected to the preliminary pump 45 through slots 69', 6.8, 69(see Figs. 2 and 6) and is also connected through slot 69 with the finalpump. The slots 69', 68' and 68 constitute the preliminary exhaust atthis stage and, as will be noted these slots are positioned as aboveexplained and the exhausting operation is continuous. In accordance withthe present construction, a leak detector 10 is provided between slots69 and 69 After the first stage of the preliminary exhaust and the abovementioned short-period connection to the final pump, the conveyor movesthe bulb over an inlet 10' for a gas filling and at slot 88 the gas isremoved. During movement over slots 69, B8 and 69 the bulb is connectedto the final pump. At the bulb may again be'flushed with gas and the gasremoved through slot 68 which slot connects with'the first orpreliminary The final exhaust is obtained by a movement of the-bulb overslots 69 68 and 69' and a final relatively long slot -68.- The closerelation of the slots as above explained, is followed with the finalexhaust slots andwhen the lamp reaches the final exhaust it may befilled with a gas at 1.0 if the lamp is to be gas-filled.

When the lamp has reached its final exhausting position B, it is tippedor sealed-off by any suitable mechanismsuch as a tipping torch of anywell known type. The mechanism for hpping off shown in'the presentdrawings is more clearly shown in copending application Ser. No.

37,111, filed August 21, 1935, by M. E. McGowan and owned bythe-assignee of the present application. With the mechanism shown, theexhaust tube is heated as it moves between fires 15. A portion of theexhaust tube is softened and is then moved between rotary disks l6 and11 which compress the softened portion and seal the bulb. When theconveyor reaches station 0, the bulb is lifted from the conveyor'andfires l8 melt off the excess portion of the tube.

The above described mechanism serves to seal the bulb while his movingwith the conveyor.

tinuous'.

As above pointed out, the presentmachine pro- I vides a valve unit whichoperates to expedite production by avoiding any stationary periods andat the same time the valve unit has the advantage of providing aneffective sealat all times whether operating as an intermittent or acontinuous machine.

Although a preferred embodiment of the invention is shown and describedherein, it is to be understood .that modifications may be made thereinwithout departing from the spirit vand scope of the invention assetforth in the anpended claims.

I claim:

1.' A valve unit for an exhaust machine for hollow bodies comprising anupper rotary valve section havinga flat surface and alower stationaryvalve section having a flat surface, said flat surfaces being disposedin contact, valve ports in said upper surface disposed on a commonradial line and in spaced relation, means connecting said spaced portstogether for simultaneous connection to a hollow body to be exhausted,arouate valve slots in said lower valve surface arranged to registerwith said ports, one of said slots being arranged to move into registerwith one of said ports when another slot moves out of register withanother port.

2. A valve unit for an exhaust machine for hollow bodiescomprising anupper valve section on different concentric circles, said slots being soarranged that as the valve sections move relatively, one port is movedinto communication with a slot as another port moves out ofcommunication with a slot, and means connecting said ports so thatthe-exhaustlngoperatioh of a ment.

3. A machine for exhausting. a hollow body comprising a rotary conveyonahead on said conveyor having an exhaust port, means for making agas-tight connection between said port and a portion of the hollow body.a rotary valve mount- 'ed on the-axis .of said conveyor, said valvehaving an upper valve section rotatable with said conveyor and a lowerstationary valve section, said valve sections having contactingsurfaces, a plurality of valve ports in ,the surface of the upper valvesection disposed on a common radial line in spaced relation, slots inthe surface of the lower valve section, one of said slots being araranged to .registerwith one of said valve ports during a movement ofsaid upper valve section, said slots being so positioned that as oneport .moves from register with .a slot-another port having a tubularextension, comprising a rotary conveyor, a head mounted on saidconveyor, an exsaid valve unit having an upper valve section and a-lowervalve section, one of said sections being rotatable with said conveyor,said uppervalve section having passages, said lower valve section havingpassages, the passages in the respective sections being so positioned asto register during relative movement of said sections, a conduitconnecting said exhaust port to the passages in said upper valvesection, gas removal means, means for connecting the passages in thelower section with said gas removal means, the oassages in said sectionsbeing so arranged that during relative movement of the sections thepassages in the respective sections are brought into register, thepositions of the registering passages being such that one pair ofopposing passages do not move completely out of register until anotherpair of opposing passages have moved partly into register.

5. An exhaust machine for lamp bulbs comprising a rotary conveyor, anexhaust 'head mounted on said conveyor, a valve unit including an upperrotary disk valve section and a lower stationary disk valve section,said sections having flat surfaces in contacting relation, means formoving said upper section with said conveyor, an exhaust port in saidhead to receive .an exhaust tube of a bulb, a conduit leading from saidexhaust port to said upper section, a pair of ports in the surface ofsaid upper section, a passage leading from said ports to said conduit,an exhaust pump, a conduit leading from said pump to said lower section,a pair of slots in the surface of said lower section, a passage leadingfrom said slots to said last mentioned conduit, said ports and slotsbeing so positioned that as the upper section moves a port is broughtinto registry with one slot as another port moves out of registry withanother slot.

6. An exhaust machine for lamp bulbs comprising a rotary conveyor, anexhaust head mounted on said conveyor, a valve unit including an upperrotary disk valve section and a lower stationary disk valve section,said sections having fiat surfaces in contacting relation, means formoving said upper section with, and about the axis of rotation of, saidconveyor, an exhaust port in said head to receive an exhaust tube of abulb, a conduit leading from said exhaust port to said upper section, apair of radially spaced ports in the surface of said upper section, apassage leading from said ports to said conduit, an exhaust pump, aconduit leading from said pump to said lower section; a pair of slots inthe surface of said lower section and disposed atdifferent distancesfrom said axis of rotation, a passage leading from said slots to saidlast mentioned conduit, said ports being positioned to span the radialdistance between said slots, and the latter so located that as the edgeof one port moves over the edge of one slot and into registry with theslot the other port moves over the edge of and out of registry withanother slot.

7. An exhaust machine for lamp bulbs comprising a rotary conveyor, anexhaust head mounted on said conveyor, a valve unit including an upperrotary disk valve section and a lower stationary disk valve section,said sections having fiat surfaces in contacting relation, means formoving said upper section with said conveyor, an exhaust port in saidhead to receive an exhaust tube of a bulb, a conduit leading from saidexhaust port to said upper section, a pair of ports in the surface ofsaid upper section, a passage leading from said ports to said conduit,an exhaust pump, a conduit leading from said pump to said lower section,a pair of slots in the surface of said lower section, a passage leadingfrom said slots to said last mentioned conduit, said ports and saidslots being so positioned that continuous communication is had betweenthe upper and the lower sections during a movement of the upper sectionfor a predetermined part of its rotary movement, the communication beingfirst between one port and one slot, and then between the other port andthe other slot.

8. An exhaust machine comprising means for supporting a hollow body, arotatable valve section and a stationary valve section, said sectionshaving surfaces in opposed relation, ports in radially spaced relationin the surface of said rotatable section, a conduit connecting saidports with the interior of said body, slots in the surface of saidstationary valve section, an exhaust pump, a conduit connecting saidslots with said pump, said ports and slots being so arranged that,during a movement of said rotatable section a predetermined distance,first one of said ports isin communication with one of said slots, andthen the other of said ports is in communication with the other of saidslots.

9. An exhaust machine for lamp bulbs including a valve comprising anupper member having a flat lower surface, and a lower member having a.flat upper surface one of said members being rotatable with respe to theother, said surfaces being in contact, one of said members havingarcuate slots spaced circumferentialiy around its flat surface andstaggered alternately on circles of different radii concentric with theaxis of rotation of said rotatable member, said other member havingports opening on its fiat surface, arranged in pairs, and spaced fromsaid axis of rotation distances corresponding, respectively, wzth theradii of said concentric circles, so that the inner ports intermittentlyconnect with said inner arcuate slots, and at other times the outerports intermittently connect with said outer arcuate slots, meansconnecting said slots to exhaust mechanism, and means connecting saidpairs of radially spaced ports together and to lamp bulbs to beevacuated, whereby said bulbs are alternately connected to saidmechanism through the inner and outer ports and arcuate slots with whichthey communicate, in order to improve the exhausting operation.

DANIEL MULLAN.

